Stupid angle? (6)

I believe the answer is:
obtuse
I believe this is a double definition.
'stupid' is the first definition.
(similar in meaning)
'angle?' is the second definition.
(obtuse angle is a kind of angle)
(Other definitions for obtuse that I've seen before include "Blunt, not sensitive" , "Angle between 90 and 180 degrees" , "Lacking in insight" , "(Of angle) between 90deg and 180deg - dull" , "Blunt or unintelligent" .)